Re: Compressed Filesystem

Chris Mason
2008-10-28T17:46:21Z

On Tue, 2008-10-28 at 10:40 -0700, Zach Brown wrote:
> > Compression is optional and off by default (mount -o compress to enable
> > it). When enabled, every file is compressed.
>
> Compression is attempted as files are written when the mount option is
> enabled, right?

Yes, and if the compression doesn't make a given set of pages smaller it
quickly backs off and goes back to writing it straight through.

>
> There isn't a background scrubber that tries to compress files which are
> already written?

No, but if you mount with compression on and use the single file defrag
ioctl (btrfsctl -d some_file) it'll compress it.

-chris